The invention relates generally to spring-activated tools, such as knives, which can be opened automatically with the activation of a release.
Automatic knives and other tools with spring loaded blades have a variety of configurations and release button designs. For example, some knives have a reciprocating (sliding) button and are referred to as having Flylock mechanisms. Existing Flylock sliding buttons generally move along the long longitudinal axis of the knife, within a cavity in the front, distal portion of the handle. As used herein, for purposes of reference only, an open knife will be referred to as oriented with its tip at its distal end and its blade edge facing upwards, to define a front left side of the handle and a rear right side of the handle. When closed, the tip will face the proximal direction with the blade edge facing downwards with a front left handle side and a right rear handle side.
The side handle portion of a flylock design knife may only be a cover plate (“scale”), and not part of the frame or mechanism. Flylock mechanisms typically have a complex multiplicity of parts, including pins, springs, levers, cams and screws that are factory assembled into a permanent unit. Typically, they are not internally user serviceable, and are not readily reconfigurable for both left-hand and right-hand activation. FIG. 5a shows a Flylock with the scale installed. FIG. 5b shows a Flylock with the scale removed. A sliding button lifts a square tip sear out of a square cut recess cavity in the blade (not shown), and a resilient member (not shown) causes the knife to automatically swing from a closed to an open position. It is closed manually.
Other knives have what is commonly referred to as a scale release, where a scale moves. FIG. 5c illustrates a conventional knife activated by the pivoting or rocking motion of an external handle scale on a knife. FIG. 5d depicts the knife of FIG. 5c, with the scale removed, showing an internal spring plate and sear bellcrank/toggle. The parts of these conventional knives require multiple fasteners and are commonly factory finished. This makes them inconvenient for users to service or reconfigure. Many conventional scale release knives have square cut sears and sear holes. These interacting parts, by nature of a factory manufacturing method, require tolerance clearance to fit together. The resulting tolerance fit leave micro-gaps in the machinery that have a cumulative effect resulting in potential blade wiggle in either open or closed positions. This is observable in surviving Flylock knives manufactured in the early 1900's, and also in modern scale release knives, as part surfaces wear with age, increasing the loose play in an “locked” blade.
These and other shortcomings in the prior art are solved by the present invention.